Core mold vent plug



Dec. 15, 1964 c. M. SMlLLlE 3,160,928

CORE MOLD VENT PLUG Filed April 2, 1963 United States Patent Office3,160,928 Patented Dec. 15, 1964 3,160,928 CORE MOLD VENT PLUG CharlesM. Smillie, Bloomfield Hills, Mich., assignor to C. M. Smillie andCompany, Ferndale, Mich., a corporation of Michigan Filed Apr. 2, 1963,Ser. No. 270,065 1 Claim. (Cl. 22-13) This invention relates generallyto air escape mechanisms for use in the production of sand blown cores,and more particularly to an easily replaceable air vent plug which isadapted to resist deformation upon the impact of approaching sand duringa core molding operation.

.of the core molds to further alleviate air that might be entrappedtherein, a typical core mold being provided with as many as from 60 to80 air vent plugs.

It has been found that it is necessary to remove and replace the airvent plugs after each successive pour due to the fact that the binderresins utilized in the core sands plug up the vent screens, thusrendering the vents inoperable for the next successive pouringoperation. Accordingly, a great deal of time and expense is incurred intransferring the core molds to a suitable tool room where the vent plugscan be easily removed. Also, the necessity for handling and transportingthe core molds interferes to some extent with the production schedule ofthe foundry.

The present invention overcomes this difliculty by providing an air ventplug which is adapted to be easily present invention to provide animproved air vent plug. adapted to be removably inserted within a sandcore mold and .which, upon being expended, can be conveniently removedto facilitate the replacement thereof. 7

Another object of the present invention is to provide an improved airvent plug having a wire mesh diaphragm and supporting means therefor toprevent any deformation of thediaphragm upon the impact of approachingsand during the core molding process.

A further advantage of the air vent of the present invention prior toits insertion within a sand core mold; I

FIGURE 3 is an enlarged plan view of the air vent plug of the presentinvention;

FIGURE 4 is an enlarged cross-sectional view taken along the line 44 ofFIGURE 3;

FIGURE 5 is an enlarged plan view of the annular retaining ring utilizedin the air vent plug of the present invention; and

FIGURE 6 is an exploded cross-sectional view similar to FIGURE 4.

Referring to FIGURE 1 of the drawing, an air ven plug 10, in accordancewith a preferred embodiment of the present invention, is shown inoperative association with a sand core mold 12 having upper and lowerend portions 14 and 16 defining a cavity 18. The air vent plug 10 isretained Within a suitable vent opening 20 by a pressed fit and effectsremoval of the air from within the cavity 18 upon the flow of sandtherein, as will be described. a

As best seen in FIGURES 2 and 3, the air vent plug 10 is provided with aperforated wire mesh diaphragm 22 adapted to preclude the escape ofsand-from the cavity 18 While permitting a free escape of air therefrom.The wire mesh diaphragm 22 is supported within the vent opening 20 by acylindrical sleeve member 24. The sleeve member 24 is provided with anannular recess 26 .disposed within one end portion thereof and adaptedto receive the periphery of the wire mesh diaphragm 22 therein. Thecylindrical sleeve member 24 is further provided with an axiallyextending flange portion 28 disposed adjacent the annular recess 26 andadapted to be crimped or otherwise formed to extend radially in- Wardover the periphery of the Wire mesh diaphragm Another object of thepresent invention is to provide an improved air vent plug of a simpledesign that can be easilyassembled and economically manufactured.

Other objects and advantages of the present invention will becomeapparent from the following detailed description taken in conjunctionwith the accompanying drawings, wherein:

FIGURE 1 is a schematic view of a sand core mold illustrating theimproved air vent plug of the present in vention in operativeassociation; A

FIGURE 2 is a perspective view of'the air vent .plug

22, as best illustrated in FIGURE 4. The axially extending flange 28 isprovided with a slightly tapered side .portion to more eflectivelysecure the diaphragm 22 to the sleeve 24 upon being crimped thereon.

An annular retaining ring 30, which is adapted to be disposed within theplug 10 directly below the wire mesh diaphragm 22, is provided tointernally support the d-i-aconvenient removal of the air vent plug 10,as will be 1 described. I 1

At such time as it is desired to remove the air vent plug ,10 fromwithin the vent opening 20', it is merely necessary to punch a hole inthe Wire mesh diaphragm 22 on either side of the bridge 32 with asuitable too-l'such as an awl or prick punch. A hook shaped tool is theninserted into the hole thus formed and engaged behind the bridge 32.Upon exerting a minimum am'ally directed force on the hook shaped tool,the plug 10 is easily withdrawn. Accordingly, it should be noted thatsince the peripheral portion of the retaining ring 30 underlies both theperiphery of the wire mesh diaphragm 22 and the crimped flangeportion.28, the complete air vent plug assembly is removed in asingleoperation upon withdrawing the ring 30. This feature obviates thepossibility of removing only the diaphragm portion of the vent plugwhile leaving the cylindrical sleeve portion remaining within the ventopening, a frequently occurring annoyance experienced upon attempting toremove air vent plugs disclosed by the prior art.

While it is apparent that the preferred embodiment herein illustrated isWell calculated to fulfill the objects stated, it will be-appreciatedthat the invention is susceptible to modification, variation and changeWithout departing from the proper scope or fair meaning of the subjoinedclaim.

What is claimed is:

An air vent plug for core boxes and the like comprising an annular bodyhaving a central'opening therethrough and an annular recess at one endof said opening defining a radial shoulder and in-turned flange meansextending from said shoulder, a wire mesh diaphragm extending acrosssaid opening with the annular marginal edge portion thereof confinedbetween said shoulder and said flange means, and a flat radiallyextending supporting ring underlying the marginal edge portion of saidwire mesh diaphragm and clamped against said shoulder by said flangemeans, said supporting ring havremoving said vent plug from the corebox, said flange means clamping and securely holding the peripheralportion of saidring during removal of said lug to assure release of saidbody and the entire plug from said box.

References Cited by the Examiner UNITED STATES PATENTS 1,236,100 8/17Nance 166-229 2,060,350 11/36 Siler 22--13 1 HER REFERENCES ModernCastings, October 1956, vol. 30, page 53 relied on. a

MICHAEL V. BRINDISI, Primary Examiner.

ing a diametrically extending bridge for supporting the central portionof said diaphragm and for providing an abutment behind which a toolinserted into said opening through said wire mesh diaphragm can beengaged for MARCUS U. LYONS, Examiner.

